Simplify PDFium by removing code that's not used in the open source repo.

core/src/fpdfapi/fpdf_render/fpdf_render_pattern.cpp

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
  
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #include "../../../include/fpdfapi/fpdf_render.h"
 #include "../../../include/fpdfapi/fpdf_pageobj.h"
 #include "../../../include/fxge/fx_ge.h"
 #include "../fpdf_page/pageint.h"
@@ skipping 863 matching lines @@
     FX_RECT rect = pShadingObj->GetBBox(pObj2Device);
     FX_RECT clip_box = m_pDevice->GetClipBox();
     rect.Intersect(clip_box);
     if (rect.IsEmpty()) {
         return TRUE;
     }
     CFX_AffineMatrix matrix = pShadingObj->m_Matrix;
     matrix.Concat(*pObj2Device);
     DrawShading(pShadingObj->m_pShading, &matrix, rect, pShadingObj->m_GeneralState.GetAlpha(FALSE),
                 m_Options.m_ColorMode == RENDER_COLOR_ALPHA);
-#ifdef _FPDFAPI_MINI_
-    if (m_DitherBits) {
-        DitherObjectArea(pShadingObj, pObj2Device);
-    }
-#endif
     return TRUE;
 }
 static CFX_DIBitmap* DrawPatternBitmap(CPDF_Document* pDoc, CPDF_PageRenderCache* pCache,
                                        CPDF_TilingPattern* pPattern, const CFX_AffineMatrix* pObject2Device,
                                        int width, int height, int flags)
 {
     CFX_DIBitmap* pBitmap = FX_NEW CFX_DIBitmap;
     if (!pBitmap->Create(width, height, pPattern->m_bColored ? FXDIB_Argb : FXDIB_8bppMask)) {
         delete pBitmap;
         return NULL;
@@ skipping 211 matching lines @@
         }
     }
     if(bStroke) {
         CPDF_Color& StrokeColor = *pPathObj->m_ColorState.GetStrokeColor();
         if(StrokeColor.m_pCS && StrokeColor.m_pCS->GetFamily() == PDFCS_PATTERN) {
             DrawPathWithPattern(pPathObj, pObj2Device, &StrokeColor, TRUE);
             bStroke = FALSE;
             bPattern = TRUE;
         }
     }
-#ifdef _FPDFAPI_MINI_
-    if (bPattern && m_DitherBits) {
-        DitherObjectArea(pPathObj, pObj2Device);
-    }
-#endif
 }